Single girl being approached by married coworker with an established open marriage

So here’s my dilemma. A couple weeks ago we got in a new guy at my job and we sort of hit it off. We really gelled like friendship wise and it was so nice to get in some new positive energy because I usually work with a bunch of jerks. He’s married and has 3.5 children, but one of first conversations brought up the fact that both him and his wife have had an open relationship since day 1. I noticed that i was interested, fascinated and wanted to know more because I’d never known anyone in real life living this lifestyle. So i thought, this might be a cool friend to have. So fast forward a couple weeks later and it seems that all the subtext between us is rapidly becoming text and my general question to everyone is if they have ever been in this situation and if they could give me advice. Did you go through with it, and was it a positive of negative experience?